rcu-tasks: Stop RCU Tasks Trace from scanning full tasks list

[linux-2.6-microblaze.git] / kernel / rcu / tasks.h

diff --git a/kernel/rcu/tasks.h b/kernel/rcu/tasks.h
index 272c905..fe05520 100644 (file)
--- a/kernel/rcu/tasks.h
+++ b/kernel/rcu/tasks.h
@@ -670,10 +670,12 @@ static void rcu_tasks_wait_gp(struct rcu_tasks *rtp)
         * and make a list of them in holdouts.
         */
        set_tasks_gp_state(rtp, RTGS_SCAN_TASKLIST);
-       rcu_read_lock();
-       for_each_process_thread(g, t)
-               rtp->pertask_func(t, &holdouts);
-       rcu_read_unlock();
+       if (rtp->pertask_func) {
+               rcu_read_lock();
+               for_each_process_thread(g, t)
+                       rtp->pertask_func(t, &holdouts);
+               rcu_read_unlock();
+       }
 
        set_tasks_gp_state(rtp, RTGS_POST_SCAN_TASKLIST);
        rtp->postscan_func(&holdouts);
@@ -1746,7 +1748,6 @@ static int __init rcu_spawn_tasks_trace_kthread(void)
                        rcu_tasks_trace.init_fract = 1;
        }
        rcu_tasks_trace.pregp_func = rcu_tasks_trace_pregp_step;
-       rcu_tasks_trace.pertask_func = rcu_tasks_trace_pertask;
        rcu_tasks_trace.postscan_func = rcu_tasks_trace_postscan;
        rcu_tasks_trace.holdouts_func = check_all_holdout_tasks_trace;
        rcu_tasks_trace.postgp_func = rcu_tasks_trace_postgp;